(a) Field of the Invention
The present invention relates to an article exchanging apparatus for use where accuracy of placement level is required. For example, it may be used for exchange of a spent anode for a fresh anode in an electrolytic furnace for aluminum.
(B) Description of the Prior Art
Heretofore, exchange of a spent anode in an electrolytic furnace for aluminum has been carried out by gripping the spent anode on the electrolytic furnace by means of an anode gripping member liftably attached to an overhead traveling crane, moving said crane to a spent anode storage location where said member releases said spent anode and then grips a fresh anode, and moving the crane back to its initial position over the electrolytic furnace so that the fresh anode may be placed at the position where the spent anode was previously placed. In this case, however, it is necessary for the exchange to ensure that the placement level of the lower surface of the fresh anode will coincide with the placement level of the lower surface of the spent anode. Heretofore, this has been done by resorting to eye measurement on the part of the crane operator. Such conventional procedure is not satisfactory in that the placement level of the fresh anode can be inaccurate and that high technique and severe attention are required of the crane operator. Moreover, fine adjustment of the placement level takes a long period of time.